JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the org.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ org/w3c/dom/css/ViewCSS.java

/*
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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/*
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 * Copyright (c) 2000 World Wide Web Consortium,
 * (Massachusetts Institute of Technology, Institut National de
 * Recherche en Informatique et en Automatique, Keio University). All
 * Rights Reserved. This program is distributed under the W3C's Software
 * Intellectual Property License. This program is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.
 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
 */

package org.w3c.dom.css;

import org.w3c.dom.Element;
import org.w3c.dom.views.AbstractView;

/**
 *  This interface represents a CSS view. The <code>getComputedStyle</code>
 * method provides a read only access to the computed values of an element.
 * <p> The expectation is that an instance of the <code>ViewCSS</code>
 * interface can be obtained by using binding-specific casting methods on an
 * instance of the <code>AbstractView</code> interface.
 * <p> Since a computed style is related to an <code>Element</code> node, if
 * this element is removed from the document, the associated
 * <code>CSSStyleDeclaration</code> and <code>CSSValue</code> related to
 * this declaration are no longer valid.
 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Style-20001113'>Document Object Model (DOM) Level 2 Style Specification</a>.
 * @since DOM Level 2
 */
public interface ViewCSS extends AbstractView {
    /**
     *  This method is used to get the computed style as it is defined in [<a href='http://www.w3.org/TR/1998/REC-CSS2-19980512'>CSS2</a>].
     * @param elt  The element whose style is to be computed. This parameter
     *   cannot be null.
     * @param pseudoElt  The pseudo-element or <code>null</code> if none.
     * @return  The computed style. The <code>CSSStyleDeclaration</code> is
     *   read-only and contains only absolute values.
     */
    public CSSStyleDeclaration getComputedStyle(Element elt,
                                                String pseudoElt);

}

⏎ org/w3c/dom/css/ViewCSS.java

Or download all of them as a single archive file:

File name: jre-rt-org-1.8.0_191-src.zip
File size: 951125 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - com.* Package Source Code

⇐ JRE 8 rt.jar - javax.* Package Source Code

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